#多级继承
class animal:
    def eat(self):
        print("chi")
    def sleep(self):
        print("睡觉")

class Dog(animal):
    def jiao(self):
        print("汪汪叫")

class erhao(Dog):
    def chaijia(self):
        print("拆家")

e1=erhao()
e1.sleep()
e1.jiao()
e1.chaijia()
